NBN Co., the operator of Australia's National Broadband Network (NBN), unveiled 12 service providers that will be the first to leverage the new network to deliver services to consumers and businesses in end-user trials. But conspicuously absent are ISPs Optus, which is not NBN-ready, and TPG, which opted out.

These trials come on the heels of two significant setbacks for NBN--the cancellation of its building tender and the resignation of Patrick Flannigan, the head of NBN Co.'s building program.

Set to begin end-user trials on the first five release sites in September, four ISPs--Telstra, iiNet, Internode and iPrimus--have completed "the on-boarding process and are NBN-ready." However, top tier ISP Optus is not NBN-ready, while TPG, which has over 500,000 ADSL2+ subscribers, has decided not to take part in the NBN.

When the trials begin in September, the four NBN-ready ISPs will connect customers to the NBN on mainland Australia then they start connecting end-users as part of the first trial that will take place in Amidale.

"The trial will extend to the other first release sites in the months following to eventually cover several hundred end-users," said Jim Hassell, NBN Co Head of Product Development and Sales in an iTWire article, adding that "this testing phase is a critical step in building the network, working with RSPs and integrating our operating systems as we aim to provide the best possible service when commercial services commence."

The other eight ISPs to take part in the trial include: AAPT, AARNnet, Comscentre, Exetel, Nextgen Networks, Optus, Platform Networks, and SkyMesh. These service providers will begin the NBN's ‘on-boarding process,' where NBN Co. works with retail service providers (RSPs) to prepare them for accessing the network.